Reverse Phase High
Pressure Liquid Chromatogra-phic Determination of
Rifampin Quinone and Hydra-zone in Anti-tuberculosis
Fixed-Dose Formulations Containing Sodium Ascorbate as
Anti-oxidant
P Umapathi*, J Ayyappan and Darlin Quine
Department of Analytical Research and Development,
Micro Labs Ltd, 67/68-A, Third Phase, Peenya Industrial
Area, Bangalore 560 058, India.
*For correspondence:
E-mail:
umpy04@yahoo.com Tel:
+91-80-28379197
Received: 11
June 2010 Revised
accepted: 17 October 2010
Tropical Journal of
Pharmaceutical Research, December 2010;
9(6):
587-593
Abstract
Purpose: To
establish the method for the analysis of rifampin
quinone and hydrazone in fixed-dose combination tablets
(FDC) containing rifampicin with or without sodium
ascorbate as an additive.
Methods: The
International Pharmacopoeial (IP) method for the
estimation of rifampin quinone in FDC was modified. The
extraction solvent (methanol/buffer mixture) of the IP
method was replaced with ethyl acetate, in order to
stabilize rifampin quinone in sample solutions of FDC
containing sodium ascorbate as an ingredient.
Results:
Rifampin quinone in FDC samples containing sodium
ascorbate, which is not detectable in the IP method, was
found to be 1.15 % (4-FDC), 1.52 % (3-FDC) and 1.60 %
(2-FDC) using the modified method. Recovery of rifampin
quinone in spiked samples of FDCs was practically nil in
IP method whereas the recovery was 99.95%, 99.39 and
99.02 % for 4–FDC, 3-FDC and 2-FDC, respectively.
Conclusion:
This modified method was suitable for the determination
of rifampin quinone in fixed-dose formulations of
rifampin both in the presence and absence of sodium
ascorbate. The method is specific, precise, accurate,
robust, rugged and gives a linear response for the
quantitative estimation of rifampin quinone and
hydrazone in fixed-dose combination tablets containing
rifampin.
Keywords: Fixed
dose combination; Rifampin quinone; Tuberculosis; Sodium
ascorbate; Quantitative determination; HPLC
